摘要:
It is possible to prepare in high yield and purity the racemic and meso forms of bridged chiral metallocenes with a stereoselective method, by synthesizing the sylil-, germyl- or stannyl-substituted ligands. These compounds can be prepared in their racemic and meso forms, and then selectively transformed in the corresponding metallocenes.
摘要:
A method of preparing supported catalysts useful for olefin polymerization is described. The catalysts comprise a Group 4 metal complex that incorporates a tridentate dianionic ligand. An activator mixture is first made from a boron compound having Lewis acidity and an excess of an alumoxane. The activator mixture is then combined with a support and the Group 4 metal complex to give a supported catalyst. The method provides an active, supported catalyst capable of making high-molecular-weight polyolefins.
摘要:
A bridged metallocene compound of formula (I) wherein: M is an atom of a transition metal; X, is a hydrogen atom, a halogen atom, or a hydrocarbon-based group; R1 is a C1-C40 hydrocarbon radical; R2 and R3, form together a condensed 3-7 membered ring; R4 is a hydrogen atom or a C1-C40 hydrocarbon radical; W is an aromatic 5 or 6 membered ring.
摘要:
Catalysts useful for polymerizing olefins are disclosed. The catalysts comprise an activator and a Group 4 metal complex that incorporates a dianionic, tridentate 2-aryl-8-anilinoquinoline ligand. In one aspect, supported catalysts are prepared by first combining a boron compound having Lewis acidity with excess alumoxane to produce an activator mixture, followed by combining the activator mixture with a support and the tridentate, dianionic Group 4 metal complex. The catalysts are easy to synthesize, support, and activate, and they enable facile production of high-molecular-weight polyolefins.
摘要:
A bridged metallocene compound of formula (I) wherein: M is an atom of a transition metal selected from those belonging to group 3, 4, or to the lanthanide or actinide groups in the Periodic Table of the Elements; X, equal to or different from each other, is a hydrogen atom, a halogen atom, a R, OR, OSO2CF3, OCOR, SR, NR2 or PR2 group; L is a divalent bridging group; R1 and R2, equal to each other, are C1-C40 hydrocarbon radical; R3 is hydrogen or a are C1-C40 hydrocarbon radical and W is an aromatic 5 or 6 membered ring.
摘要:
A bridged metallocene compound of formula (I) wherein: M is a transition metal; X, is a hydrogen atom, a halogen atom, or a hydrocarbon group optionally containing heteroatoms; L is a divalent bridging group; R1 is a linear C1-C40 hydrocarbon radical optionally containing heteroatoms; T1 and T4 are a oxygen, sulfur atom or a C(R18)3 group; wherein R18, are hydrogen atoms or a C1-C40 hydrocarbon radical; T3 and T4 are C1-C40 hydrocarbon radicals; R4 is a hydrogen atom or a C1-C40 hydrocarbon radical; W is an aromatic 5 or 6 membered ring.
摘要:
A bridged metallocene compound of formula (I) wherein: M is a transition metal; X, is a hydrogen atom, a halogen atom, or a hydrocarbon group optionally containing hetematoms; L is a divalent bridging group; R1 is a linear C1C40 hydrocarbon radical optionally containing hetexoatonis; T1, T2, T3 and T4 are an oxygen or sulfur atom or a C(R18)2 group with the proviso that at least one group between T1 and T2 is an oxygen or a sulfur atom; wherein R18, are hydrogen atoms or a C1-C40 hydrocarbon radical; n is 1, 2 or 3; R4 is a hydrogen atom or a C1-C40 hydro carbon radical; W is an aromatic 5 or 6 membered ring.
摘要:
A compound of formula (X): wherein R1, R2, equal to or different from each other are hydrogen or a linear or branched saturated or unsaturated C1-C20-alkyl, C3-C20-cycloalkyl, C6-C20-aryl, C7-C20-alkylaryl or C7-C20-arylalkyl radical, optionally containing heteroatoms belonging to groups 13-17 of the Periodic Table of the Elements; or they can form a C4-C7 ring optionally containing O, S, N, P or Si atoms that can bear substituents; R3 is hydrogen or a linear or branched saturated or unsaturated C1-C20-alkyl, C3-C20-cycloalkyl, C6-C20-aryl, C7-C20-alkylaryl or C7-C20-arylalkyl radical, optionally containing heteroatoms belonging to groups 13-17 of the Periodic Table of the Elements; or two adjacent R3 groups can form a C4-C7 ring optionally containing O, S, N, P or Si atoms, wherein said ring can bear substituents; and at least one of R1, R2 or R3 is different from hydrogen.
摘要:
A process is disclosed for preparing bis-cyclopentadienyl compounds bridged by a single carbon atom by reacting a carbonyl compound with a cyclopentadienyl compound in the presence of a base and of an oxygen-containing solvent having an atomic ratio carbon/oxygen not higher than 3. The compounds obtainable in high yields with this simple single-step process can be used to prepare ansa-metallocenes which are active as catalyst components in the polymerization of olefins.
摘要:
Catalysts useful for polymerizing olefins are disclosed. The catalysts comprise an activator and a Group 4 metal complex that incorporates a dianionic, tridentate 2-(2-aryloxy)quinoline or 2-(2-aryloxy)dihydroquinoline ligand. In one aspect, supported catalysts are prepared by first combining a boron compound having Lewis acidity with excess alumoxane to produce an activator mixture, followed by combining the activator mixture with a support and the tridentate, dianionic Group 4 metal complex. The catalysts are easy to synthesize, support, and activate, and they enable facile production of high-molecular-weight polyolefins.